I tried setting the datadir=/Volumes/BLOCKCHAIN (which is the path to my external drive). Then I ran bitcoind and this is the end of the output, right before it kicks my drive out and gives me a Bus error: 10.
...
2019-10-22T16:30:26Z init message: Loading block index...
2019-10-22T16:30:26Z Opening LevelDB in /Volumes/BLOCKCHAIN/blocks/index
2019-10-22T16:30:26Z Opened LevelDB successfully
2019-10-22T16:30:26Z Using obfuscation key for /Volumes/BLOCKCHAIN/blocks/index: 0000000000000000
Bus error: 10
Is there another way I can achieve this?